Database Users

2nd Core App Questions

so now that the latest beta of siyah kernel supports enabling/disabling of the 2nd core, and tegrak already released an app for it, i just want to know the possible effects in performance/battery if you use the different options of the 2nd core app.. especially when we use the single core option.. so what will happen to our phone when we run HD games, and im sure that it will extend the battery life, just not sure how the phone will behave with only 1 core running.. and will it be bad for our phone to only run at a single core..
and also, am i right to assume that our phone has the option "dynamic hotplug" by default?

Shouldn't see much of a decrease in the performance. The sgs has a single core yet the cpu can still handle anything thrown against it. Point being there is nothing out that demands dual core performance. On another note note, hd games are not actually gd. It is just advertising point for game developers.
$1 gets you a reply

Using one core instead won't break your cpu. It gonna make your phone cooler ( ! core is running producing less heat and the heat dissipator is made for the dual core ) and have a better battery life obviously. It will, obviously too, slow down your phone, but the speed lost is to be determined. You might want to test it out to see if it's getting laggy or simply suck. As already said, the SGS I has a 1Ghz proc and can handle most of the top recent content available so with a 1.2 Ghz single core, you should be able to handle everything available, specially with an optimized kernel like siyah. And you are right, the default mode is dynamic hotplug, which use both core when needed and turn the core 1 ( 2nd core ) off when not needed.

I tried playing a little with it. The overall smootness doesn't change and i get about the same fps in nenamark2. The only game i saw stuttering a little more in single mode was Shadowgun, the others are just the same. I also have the feeling that cpu noise is reduced while playing music through headsets when you run on single.

I like the idea of switching off one core. But while using only one core this leads to a higher load on that corse. This will result in higher frequencies an thus higher battery consumption?
So might using only one core even be worse for battery life?
I mean isn't that the reason why you use multiple cores? That one does not have to produce cpu with high frequencies? I think I once read that the energy a cpu uses it proportional to the frequency squared. So it is not a linear relation. That means two cores on 500 MHz are using less power than one cpu on 1000 Mhz. Can someone confirm that? So if th os is optimized for multiple cores the energy consumptions will be less.
What do you think or know about Android. Is it managing two cores intelligently an thus reducing energy consumption or are we doing better with switching off one core?

Hi,
is anybody out there who can share any experiences with this 2nd Core app?
It would be very interesting whether it really saves battery(and if yes, is it noticeably or is it a huge difference)? Are there any negative effects in speed oder stability?
Rgds

I don't particularly care about potential battery saving, but I use it to manually disable one core while playing games which have problems with SoundPool ( see http://code.google.com/p/android/issues/detail?id=17623 ), such as Galcon, as this mitigates the problems.

Schindler33 said:
I like the idea of switching off one core. But while using only one core this leads to a higher load on that corse. This will result in higher frequencies an thus higher battery consumption?
So might using only one core even be worse for battery life?
I mean isn't that the reason why you use multiple cores? That one does not have to produce cpu with high frequencies? I think I once read that the energy a cpu uses it proportional to the frequency squared. So it is not a linear relation. That means two cores on 500 MHz are using less power than one cpu on 1000 Mhz. Can someone confirm that? So if th os is optimized for multiple cores the energy consumptions will be less.
What do you think or know about Android. Is it managing two cores intelligently an thus reducing energy consumption or are we doing better with switching off one core?
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totlly agree

The notes dual cores

Are they true dual cores and run at the same time? My evo 3D is dual core but the second core only kicks in when needed so I don't consider it true dual core. Do our cores run simultaneously or like the evo 3D?
Sent from da BEST (Galaxy Note)

Why do you think the way EVO 3D works is inferior? AFAIK, they all work in similar fashion to reduce battery consumption.
Without ICS, all Java based Android apps can only use one single core anyway. Only native apps (like 3D games) can take advantage of dual-core. That's the limitation of Dalvik JVM for Android 2.xx. You will need Android 3.xx or higher to get dual-core support on JVM.

sprintuser1977 said:
Are they true dual cores and run at the same time? My evo 3D is dual core but the second core only kicks in when needed so I don't consider it true dual core. Do our cores run simultaneously or like the evo 3D?
Sent from da BEST (Galaxy Note)
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Power saving allows the 2nd core to go into sleep mode, even at fully idle in 200Mhz mode it consumes power and yes its a true dualcore. If you wan you can have both cores running at 1400Mhz 24/7

In power saving mode,I get a quadrant score of only 2600 compared to 3800-4500 with power saving off.
I definitely agree that the Note shuts down one core in power saving mode.
On my wifes s2,power saving mode scores around 3200.Power saving off gets around 3400.Not much difference.

sprintuser1977 said:
Are they true dual cores and run at the same time? My evo 3D is dual core but the second core only kicks in when needed so I don't consider it true dual core. Do our cores run simultaneously or like the evo 3D?
Sent from da BEST (Galaxy Note)
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It's called dynamic hotpluging and yes that is how the Exynos works. Why would you want both running all the time?
If you want the ability to have both constantly on, search for tegrak's dual core app in the market. You can force both on with that. You may need kernel support though.
Sent from my GT-I9100 using xda premium

(q)can you disable quad core?

Is or possible to disable quad core on this phone? I can see that s3 handles everything done with dial core

comc49 said:
Is or possible to disable quad core on this phone? I can see that s3 handles everything done with dial core
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Even HTC G1 can get things done, with a half a core free to eat pop corn.
To your question, if you are patient enough then there should be safe and easy way very soon.

Yes, it is possible.
Root the phone and then echo 0 > /sys/devices/system/cpu/cpu#/online, where # is the number of the core you want to take offline.
As for governers that automatically hotplug cores on and off, we will have those soon enough.

comc49 said:
Is or possible to disable quad core on this phone? I can see that s3 handles everything done with dial core
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But why? I'm curious to why.... One would think that ox you're going to do that... Just get a non quad core phone.
Sent from my Nexus 4 using xda premium

Locksmith81 said:
But why? I'm curious to why.... One would think that ox you're going to do that... Just get a non quad core phone.
Sent from my Nexus 4 using xda premium
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But then you don't get that fancy Adreno 320 GPU with a standard dual-core phone

jacklebott said:
But then you don't get that fancy Adreno 320 GPU with a standard dual-core phone
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And you'll always have the option to enable all 4 cores.
Sent from my Nexus 4 using xda premium

+ battery life

Isn't 4 cores better for battery life because the amount of work is spread between them, eg. if the system is running on 4 cores @ say 1Ghz, but if you're using two cores, then it might be higher CPU usage on the two cores.

parker09 said:
Isn't 4 cores better for battery life because the amount of work is spread between them, eg. if the system is running on 4 cores @ say 1Ghz, but if you're using two cores, then it might be higher CPU usage on the two cores.
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you can just use Setcpu to underclock your phone. no need to shutdown any cores. you just need to be rooted and install Setcpu. i did this and i noticed how much battery life i had afterwards. besides, there is no lag by underclocking it down.

As to my knowledge, turning off cores does not save any more battery. I believe the whole CPU is powered as a whole. Now like the guy said above, 4 cores running at 486MHz is a lot more battery efficient than scaling the processor to 702MHz for one core.
Reason being the cpu has to turn up the clock speed, which increases the voltage used by the CPU.
Also, if you're looking to save battery, undervolting is far better than disabling cores.

qwahchees said:
As to my knowledge, turning off cores does not save any more battery. I believe the whole CPU is powered as a whole. Now like the guy said above, 4 cores running at 486MHz is a lot more battery efficient than scaling the processor to 702MHz for one core.
Reason being the cpu has to turn up the clock speed, which increases the voltage used by the CPU.
Also, if you're looking to save battery, undervolting is far better than disabling cores.
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On another thread it seems that you can under volt by a large margin with I'll effects.
Not got n4 yet but if its anything like the n7 you should be able to under clock quite a bit before it becomes noticeable.
Sent from my Nexus 7 using Tapatalk 2

Faux 005 kernel using Intellidemand governor disables the 3 cores when not needed, and then turns them back on when needed (hotplug)

qwahchees said:
As to my knowledge, turning off cores does not save any more battery. I believe the whole CPU is powered as a whole. Now like the guy said above, 4 cores running at 486MHz is a lot more battery efficient than scaling the processor to 702MHz for one core.
Reason being the cpu has to turn up the clock speed, which increases the voltage used by the CPU.
Also, if you're looking to save battery, undervolting is far better than disabling cores.
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I think this is correct, I'm learning about computer architecture now in class and from what I understood it's like this. If I were to build a house by myself it would not only take longer to finish but I would also be more tired when I did as opposed to sharing all the tasks with 3 other people. Also note that everyone(4 people) would have more energy left over for other tasks when the house is finished. I haven't finished this chapter yet so don't quote me lol.

Nexus4 cores come back online, even when disabled!
Ranguvar said:
Yes, it is possible.
Root the phone and then echo 0 > /sys/devices/system/cpu/cpu#/online, where # is the number of the core you want to take offline.
As for governers that automatically hotplug cores on and off, we will have those soon enough.
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So, I tried disabling Nexus4 cores using this above method after rooting, but the cores come back online as soon as I start running any app. Is there any other workaround that needs to be done for this device. I was able to use this method successfully on my older devices though.
Has anyone had success with N4?

Four cores are never on at the same time with regular use... Two are
Sent from my Nexus 4 using xda app-developers app

comc49 said:
Is or possible to disable quad core on this phone? I can see that s3 handles everything done with dial core
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Wow. That's like disabling one of your testicles!!!
Sent from my Nexus 4 using xda app-developers app

I have only dual core mode, check my signature. Franco Kernel
Sent from my Nexus 4 using xda premium

[Q] Nexus 7 Quad Core and Single Core Mode?

While reading anandtech's review for nexus 7, It says "The only difference is that CPU clocks are 1.15 GHz for all four cores at 100%, or 1.3 GHz on a single core." Does this mean if I underclock my nexus 7 to 1.2ghz I'll be able to use all cores? Thanks in advance!

What the review is stating is that with standard rom and kernel from google its settings mean that it can only work at 1.15ghz on all four cores at once, with other kernels you can overclock this to be more at once or less depends what kernel you choose. Tbh mostly you wont notice a difference unless benchmarking but what use is a benchmark Id say you should judge a device by using it not by what a test tells you

My ze551kl Asus zenfone 2 laser's octa core isn't working correctly..

So as you can see by these screenshots only 4 of my eight cores are working.. Is there any way to fix this??
(Here's the album i mgur. c 0 m/ a /2FWDH
Any help would be extremely appreciated..

gyropepsi said:
So as you can see by these screenshots only 4 of my eight cores are working.. Is there any way to fix this??
(Here's the album i mgur. c 0 m/ a /2FWDH
Any help would be extremely appreciated..
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What makes you think that only 4 cores are working?
I don't know in the Android world, but in PCs the applications must be written expressly to use more than one core. And the SD 615 has 4 cores that runs at 1.7 MHz max and the other 4 at 1.0 MHz max, but the frequencies could be lowered by phone makers to increase battery duration.

BubuXP said:
What makes you think that only 4 cores are working?
I don't know in the Android world, but in PCs the applications must be written expressly to use more than one core. And the SD 615 has 4 cores that runs at 1.7 MHz max and the other 4 at 1.0 MHz max, but the frequencies could be lowered by phone makers to increase battery duration.
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Yeah but I had my phone on performance mode and it's using half of the cores, if the other 4 max at 1.0mhz then why are all games that I play (3D Wise) are slow? Is there any way I could fix it? Could overclocking via CPU managing apps (using root,) work in my situation?

gyropepsi said:
Yeah but I had my phone on performance mode and it's using half of the cores, if the other 4 max at 1.0mhz then why are all games that I play (3D Wise) are slow? Is there any way I could fix it? Could overclocking via CPU managing apps (using root,) work in my situation?
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Four cores are high-performance, and four cores are low-power. The performance cores suck up a lot of battery, so not for use with background tasks. The low-power cores are useless for pretty much anything but background tasks, so they're not for use with gaming, etc. The fact that your apps are only using four cores is normal.
Also, as for your gaming performance, I've actually done some testing on this and it turns out that on the ZE551KL, the GPU is way underpowered. No amount of overclocking can fix the abysmal GPU performance on the ZE551KL. This doesn't seem to happen on other models, either, so... yeah.

@gyropepsi: yes, that's correct, the eight cores are not "equal". You have four cores for general CPU use and another four for higher CPU use. They cannot be used in the same time, they get switched to save power. It's actually called "dual quad-core".
https://www.qualcomm.com/documents/snapdragon-615-processor-product-brief
Other manufacturers have one core for low processing and four for high processing. Those phones are doing great in tests but they really suck in daily usage.
@sensi277: I would't say abysmal performance, but yes, it seems to be lower than the Selfie in some tests. However it moves VERY good for a phone, 3D tests on phones are just for kids, to brag about their phones. Nobody does real gaming on a phone.

SoNic67 said:
@sensi277: I would't say abysmal performance, but yes, it seems to be lower than the Selfie in some tests. However it moves VERY good for a phone, 3D tests on phones are just for kids, to brag about their phones. Nobody does real gaming on a phone.
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?
Except, I do real gaming on my phone. Or at least, I try to. Laser GPU holds back most games, though.

Why? You don't have a laptop, desktop? Phone gaming experience is horrid no matter what. No good controls, no immersion...
Sent from my ASUS_Z00TD using Tapatalk

Here is some info about big.LITTLE processing:
https://www.arm.com/products/processors/technologies/biglittleprocessing.php
Sent from my ASUS_Z00TD using XDA-Developers mobile app